A new technique, nano-imprinting, is disclosed for forming a nanometer-sized structure on a surface of an article by impressing directly a structure having protrusions on a working object, being different from conventional lithography utilizing a light beam or an electron beam (U.S. Pat. No. 5,772,905).
In this technique, as shown in FIGS. 9A to 9D, stamper 100 having a protrusion pattern 103 of a size of tens or hundreds of nanometers formed by an electron beam or the like is impressed on thin resin film 104 formed on flat substrate 105 and then detaching the stamper therefrom to form a projection-depression pattern: depression portion (molded region) 106 of the resin film is removed by reactive ion etching or a like method; and substrate 105 is etched by utilizing the unremoved remaining resin layer 107 as the mask to form structure 107, 108 having nano-metric projection-depressions corresponding to the original stamper. In this method, to prevent the deterioration of the stamper by impression operation, the impressing action is stopped before top face 141 of protrusion 103 of stamper 100 comes into direct contact with substrate 105 carrying thin resin film 104, and the stamper is detached. In this method, even if the impressing action is stopped before the protrusion top face of the stamper comes into direct contact with the substrate, the resin of the thin film can rise by the impression to come into contact with bottom face 142 of the depression portion of the stamper.
This contact may make irregular the formed protrusion-depression structure of the thin resin film on detaching of the stamper from the thin resin film.
The present invention intends to provide a structure having holes at desired positions.